Caisson for subaqueous work.



Patented Mar. u, |992.

(L BLAGBURN.

[IMSSON FOR SUBMIUEUUS WORK.

(Application led Kay 9. 1901,)

Y ing partly insection'.

I UNITED STATES PATENT OFFICE.

CHARLES BLAGBURN, OF SAN FRANCISCO, CALIFORNIA.

CAISSON FOR lsueeeueousl week.

SPECIFICATION forming part of Letters Application filed May. 9, 1901.

To @ZZ whom it may concern:

Beit known that I, CHARLES BLAeBUnN, au citizen of England, residing in thevcity and county of San'Francisco, State of California, have invented certain new and yuseful Improvements in Caissons for Snbaqueons Work; and I do hereby declare'the following to be a full, clear, and exact description of the same.

The present invention is more especially ap- 1 The letter Aie used to indicate the caisson. (Shown in Fig. 1 of the drawings-as being submerged and rests upon the bottom or rive'rbed A'.) Said caisson is provided with an entrance-tube B, communicationv being estab-r lished between the interior of the casing and the entrance-tube by a hinged air-lock door B. The entrance'tube maybe said to constitute a continuation of the'air-lock @which lock is closed by the vertically-movable airlock door C'. In gaining admission to the air! lock it is necessary to admit of a person entering therein. l/Vhile saiddooris opened the airlock door B is held upward, so as to close co1n` munication between the entrancetube and interior of caisson. This is to prevent .the escape of air from within the interior ofl the caisson. After the door C' has been closed then the, door B is swung open, so as to permit of entrance being had to the interior of the caisson.

Air under pressure is supplied to the interior of caisson by supply-pipe C2, which supply-pipe leads from any suitable source of power. (Not shown.)

lVithin the caisson at any convenient point is arranged a hopper E', to which is connected Patent No. 694,939, dated March 11, 1902. Serial No. 59,438. (No model.) l

4within the hopper E to a point 'near its bottube E extends above the waterline for a short distance, so that thek water therein` will 4be such as toresist the air-pressure within the caisson. Asv the caisson is submerged the water is forced therefrom by the pressure of the air therein, the pressure of which mainor level. tube forms a perfect Water seal,within which the hereinafter-described.discharge mechanism works and which prevents the escape of air from within the caisson.

`Near the bottom of the hopper is arranged the chain-wheels 2,0ver which travel the endless chain carriers `3. These carrierswork within the seal-tube E and over guide-wheels .4 and chain-wheels 5,held within frame 6. To the endless carriers the buckets 7 are attached yat proper intervals.'` These buckets and chains constitute an endless chain and bucket elevator.

The shaft S, yto which the chain whee1s 5 are secured, is driven by-means of a belt working over belt-wheel F', attached to said shaft. The belt is driven from any suitable power mechanism. (Not shown.)

v The workman located inside ofthe caisson ihrowsthe excavated material'directly into the hopper E', there being a grid G arranged to catch or hold back `boulders too large to be raised by the endless chain and bucket elevator. Such material as passesthrou gh the grid falls to the bottom of the hopper and is takenl ,up by the buckets 7 during the travel of the endless carrier and carried upward through the water-seal tube and over the chain-wheels 5. As carried over these chain-wheels the chute Il, by means of which it is deliveredto a suitable place of deposit. If the material thus removed from the river-lmttom be goldbearing, the same is ydischarged by the chute into 'a suitable receptacle, from which it is taken and treated in order to recover the valuable particles. Y v

The chain-wheels 2 are mounted iii-slidebearings, which are controlled by the take-np mechanism 9. By means of this take-u p mech I tube E. One portion of the tube extends l Y' tom,'said extensionV forming a Wall 1. The

tains the water inthe tube E at a given height 1 The' water thus contained `in the material contained therein is discharged into -thereof being attached to one end of a fulcrumed lever K. The inner or free .end of i said lever is connected to the outlet-valve a of water-supply tank K by means of chain a. The outlet b of'this tank communicates with water-sealtubeE. Consequentlythemoment the Water in said tube has fallen below a given point the float descends and draws therewith the float-rod and lifts the valve a, so as to unseal or open same and permit the water to flow into the water-seal tube, thus maintaining the water therein at approximately a given level. It will -be understood that as the water reaches the proper level in the water-seal tube that the oat raises and the outlet-valve of the supply-tank is closed.

For the purpose of raising or removing boulders froml Within the caisson the wire rope or cable L is employed. This cable extends through the air-lock O and is provided at one end with a hook L', by means of which the cable is fastened around the boulders. However, any suitable means may be employed for the removal of boulders or the like, that illustrated being the simplest for the purpose.

The essential feature of the invention resides in the employment of discharge mechanism for the excavated material in combination with the water-seal closure between the interior of the caisson or working compartment and the discharge of the excavated material.

Having thus described the invention, what is claimed as new, and desired to be protected by Letters Patent, is`

l. A caisson having iu combination a Working chamber, a Water-sealed U-shaped discharge-conduit suspended from a point above the working chamber, one arm of said cham-l ber extending without said chamber and the other arm being supported by the lower ond ofthe said Iirst-mentioned arm and opening within the working chamber.

2. Acaisson, having in combination, a Working chamber having an open lower end, a water-'sealed conduit extending from the working chamber to a point above the level of'the water and means for automatically varying the height of the water column controlling the water seal, substantially as set forth.

ing chamber having an open lower end, a discharge-conduit extending from the working chamber to a point above the level of the water and provided, within the working chamber, with a receiving branch having an open upper end and means for automaticallymaintaining the Water Within the conduit at a height not less than the level of the water outside of the conduit, substantially as described. l l

'4. The combination with a caisson for subaqueous work having an opening in its lower portion, of av receiving-hopper for the excavated material, a water-seal conduit integral with said hopper, and a chain and bucket carrier adapted to work through said conduit for removing the excavated material, substantially as described.

5. The combination with a caisson for subaqueous work, of a receivinghopper for the excavated material, a water-seal tube connected therewith and projecting beyond the caisson above the water-line and an endless chain and bucket vcarrier working therein and through the water seal for the removal of the excavated material.

6. The combination with a caisson for subaqueous Work, of a water-seal closure for the outlet of the excavated material, including a hopper and a conduit secured together, anda chain and bucket conveyer working through said water seal for the removalot the excavated material.

7. The combination with acaisson for subaqueous work, of a water-seal closure for the outlet ofthe excavated material, devices Working through said water seal which receive and remove the excavated material, and means whereby the water seal is automatically maintained at approximately a given level.

S. The combination with a caisson forvsubaqueous work, of a receiving-hopper for the excavated material, a tube secured thereto and projecting beyond the caisson above the water-line, a water seal Within said tube and hopper, means for automatically maintaining the water seal at approximatelya given level, and devices working throughthe Water seal Afor removing the excavated material from `within the ore-receiving hopper.-

In witness Whereofl have hereunto set my hand.

CHARLES BLAGBURN.

Witnesses:

WALTER F. PAUL,

D. B. RICHARDS.

3. A caisson, having in combination, a work- IOS IIO 

